Cal V (WLP051) Sluggish/Stuck Ferment

I need some help and/or opinions for kicking a Cal V yeast back into action. I brewed an APA...actually...IAPA:cross: since my efficiency ended up around 85% rather than my planned 72%

Batch size ~10.5 gal
OG - 1.064
60 minute sac rest at 151F
Mash Ph 5.4
Wort Ph 5.2
Aerated wort with fish tank pump and filter thru .5 micron stone ~20 minutes.
Pitched (2) 0.5L starters of WLP051 @ 63F and allowed to free rise to 68F over 2 days
Fermenter: Blichmann 14gal TC conical

Since I'm fermenting in the conical I rely on the air lock for signs of activity. Saw activity within 12 hours and went "vigorous" within 24 hours. After 5 days activity slowed down, so I took a sample at 1.028. At day 7 (today) took another sample at the same 1.028.

I'm worried that while still active, it is slowing significantly and possibly stalling out. So, I'm looking for opinions to get this thing going again. Should I:

1) Rouse the yeast by blowing CO2 through the racking arm (waiting on replacement of lost gasket due to arrive tomorrow)
2) Add yeast hulls (on hand)
3) Add yeast hulls and rouse the yeast
4) Add a WLP001 starter at peak to clean up after the WLP051

I've heard this yeast is somewhat temperamental. I've never used yeast hulls. Do they require hydration? I can't imagine they do since they are not alive. Thanks for any suggestions.

I would go with option 1. I just fermented an IPA with WLP051 that stalled at 1.021 for a couple days. I roused the yeast and it ended up finishing at 1.015 (78% attenuation).

Agree with above. I have a 14 gallon stainless conical and had to shake/rock my last batch with WLP051. It dropped 6 more points (1.020->1.014) after a gentle rousing and some patience. Also be sure you are getting a good sample. Sometimes I find I need to disregard first sample. I'm notice wort in sample valve may not ferment as readily as bulk in fermenter from my experience.

My tri-clamp gaskets showed up today, so I hooked up the CO2 tank to the racking arm and blew the CO2 into the bottom of the fermenter for 20-30 seconds. I will check the gravity again in a few days. I hope that helps blow off some of the sulfur too.

Probably stupid question, but how do you get CO2 in through port. I don't understand how you prevent beer from flowing out as you try to introduce gas.

Not sure if you read through the White Labs website for that yeast, but there is some discussion on stuck ferments: http://www.whitelabs.com/yeast/wlp051-california-ale-v-yeast

... It basically ceases to ferment if the temp drops much below 64F. Above 72F it gets a bit estery.

Click to expand...

... For best results try to keep it below 68 and you should be good.

Click to expand...

Hope that helps a little. I did an IPA that fermented all the way out to expected FG at 66 F.

dermotstratton said:

Probably stupid question, but how do you get CO2 in through port. I don't understand how you prevent beer from flowing out as you try to introduce gas.

Click to expand...

I have a spare gas line with a check valve in it. Honestly, I haven't even needed the check valve. I hook up the line to the racking arm port, turn the port down so it's pushes gas to the bottom, remove the relief valve from the top of the fermenter, turn on the gas to 7-8 psi, then open the racking arm valve. The gas force is strong enough to keep the beer from flowing out. When complete, I close the valve first then shut off the gas.

241 said:

Not sure if you read through the White Labs website for that yeast, but there is some discussion on stuck ferments: http://www.whitelabs.com/yeast/wlp051-california-ale-v-yeast

Hope that helps a little. I did an IPA that fermented all the way out to expected FG at 66 F.

Click to expand...

I read through the reviews, and heeded most of the cautions given. I think my issue stems from my higher efficiency. Since my OG was 8 points higher than what I expected I most likely under pitched. It's in the expected attenuation zone now at least.

After rousing the yeast I have the FG down to 1.018. Still a few points higher than what I want. I am fighting the urge to add a small pitch of WLP001. I plan to wait another week, then cool it to 63F, dump the yeast, dry hop and call it a beer.

How did you like the yeast in the IPA? Did you have any issues with sulfur aroma?